Sewing machine



Oct. 15, 1940. G. A. FLEKENsTElN y2,217,895

SEWING MACHINE @www Oct. 15, 1940. G'. A. FLi-:cKl-:NSTEIN 2,217,895v

SEWING MACHINE Filed Sept. 28, 1939 I 4 Sheets-Sheet 2 Syvum/vbo@ Oct. 15, 1940. G. A.f-F| EcKENsTE|N 2,217,895

SEWING MACHINE Filed Sept. 28. 1939 4 Sheets-Sheet 5 FIG. 3

552y Je 53 54 45 Oct. 15, 1940. G. A. FLECKENSTEIN SEWING MACHINE Filed sept. 28, 1939 4 sheets-sheet 4 Geo/ge. l/C-/e cke/7s fem @www Patented Oct. 15, 1940 VPATEISVI oFFlcE SEWING MACHINE George A. Fleckenstein, Stratford, Conn., assignor to The Singer Manufacturing Company,

Elizabeth, N. J., a corporation of New Jersey Application September 28, 1939, Serial No. I296,8'11

4 Claims.

This invention relates to sewing machines, more particularly of the small, portable, electrically driven type for family use.

Machines of this type are commonly constructed with a iiat box bed and overhanging bracketarm; the main-shaft and its driving motor being located in the box bed.

A modern lock-stitch family sewing machine requires a bobbin-thread and loop-taker mechanism which will run smoothly, quietly and eiliciently without annoying vibration. It is also a desideratum that the bobbin be readily accessible for replenishment. These requirements are f ullled by a loop-taker of the vertical axis two-toone rotary hook type, such as used in the present machine embodying the invention.

The invention has for an object to provide a portable electric lock-stitch family sewing machine of simple construction, the elemental mechanisms of which are of proven types and are so arranged and related as to require but few parts for their actuation.

The invention has for a further object the provision of a simplified gearing and shaft arrangement for a box bed family machine driven by a small high speed motor disposed in said bed, the machine having a balance-wheel which is beltdriven by said motor and is small enough to clear the table on which the machine may be stationed for use.

The invention is concerned with attaining the above objects whileinterconnecting various machine shafts in the box bed for rotation at the proper relative speeds for actuation of the several elemental mechanisms of the machine, namely, the needle-bar mechanism, the rotary-hook mechanism and the work-feeding mechanism.

In the accompanying drawings, Fig. 1 is a longitudinal vertical section through a sewing machine embodying the invention. Fig. 2 is a bottom plan view of the machine. Fig. 3 is a transverse vertical section through the machine bed on the line 3-3, Fig. 2, with the bracket-arm headin elevation. Fig. 4 is a section on the line 4--4,

Fig. 2, and` Fig. 5 is a vertical section transversely head I2 for the usual needle-bar I3 ,and springpressed presser-bar I4. l

Journaled in the bed I, in the internal boss I5 on the end wall 4 and in the internal bearing bracket I6, is the main-shaft I 'I the outboard projection of which carries the hand-wheel and pulley member I8 which is connected by the belt I9 to the motor pulley 3.

Journaledl in the bracket-arm II is the top rotary shaft which, as usual, drives the needle- 10 bar I3 and take-up 2l. The top shaft 20 is geared one-to-one to the vertical shaft 22 which, in turn, is geared one-to-two .to the main-shaft II, so that the main-shaft I'I makes two complete Arotations to one rotation of the top shaft 20 which l5 eiects one complete reciprocation of the needlebar I3 or one stitch-forming cycle.

Mounted on the inner end of the main-shaft Il is a spur-gear 23 which meshes with the spurgear 24 on the countershaft 25 journaled vertigo cally below and parallel to the main-shaft I1 in the bearing bracket I6 andtransverse intemal bed-partition 26. Thegear 24A is 'of the same 4pitch-diameter as the gear ,23 but'has double the face width, as shown in Fig. 1, so that thecoun- 25 tershaft 25 runs at the same speed as the mainshaft Il.

The countershaft 25 is connected by the oneto-one spiral bevel-gears 21 to the vertical hookshaft 28 which is journaled in the lbushing 23 30 in the bed-bracket 30 and carries the usual rotary loop-taking hook 3| in which the usual stationary 'bobbin-thread case and bobbin (not shown) are located. Thus, the rotary hook 3l is driven two revolutions per stitch-forming cycle, as is usual with loop-takers of this type.

Journaled at the side of the plane of the axes of the shafts I1 and 25 is the feed-shaft 32 which carries'the usual feed-lift eccentric 33 and feedadvance eccentric 34. The feed-lift eccentric 33 a lifts the feed-bar 35 which carries the feed-dog 36 and is slidingly fulcrumed on the stationary feed-fulcrum pin 31. The feed-advance eccentric 34 is engaged by the-curved lever 38 which is fulcrumed at 39 on the transverse partition wall 26 45 and is engaged by the push-bar 40 fulcrumed at 4I on the feed-bar 35. A feed-regulating lever 42 is fulcrumed at 43 on the partition wall 26 and, at one end, carries a pin 44 which enters a slot 45 in the push-bar 40. The other end of 50 the feed-regulating lever 42 projects through the slot 46 in the front wall 2 of the bed and is accessible to the operator. The inner end of the lever 42 is slightly sprung or bent to drag upon the face of the partition wall 26 sufficiently to 55 -in U. S. Patent N0. 1,916,860, dated July 4, 1933.

The feed-shaft 32 in the present machine 'carries a spur-gear 4l which meshes with the gear 24 on the countershaft 25 and is double the pitchdiameter of the gear 24 so that the feed-shaft will make ione. revolution per stitch-forming cycle. The gears 48 and 23, both of which mesh with the wide faced gear 24 are laterally odset 'from ,one another so that they will not. conflict.

There is thus attained a simple and unique arrangement of shafts and gearing for driving the essential and proven mechanisms of a verticalaxls rotary-hook sewing machine from a mainshaft journaled in the box-type bed of the machine which contains the high speed electric motor for driving the main-shaft at the proper speed, using a balance-wheel of the moderate size necessary to clear the machine-supporting table.

'I'he bracket-arm II and top-shaft 20 are set vertically over the main-shaft I1 which is set forwardly of the longitudinal center line of the bed. The motor 1 is set rearwardly of the main-shaft I1 suillciently to permit the use of a belt I9 of adequate length for eiective'driving engagement with the belt-pulleys 8 and I8. The feed-shaft 32 is disposed in the proper relation to the feedbar 35 to actuate the latter from the feed-eccentrics 33 and 34 and permit of regulation of the stitch-length.

Having thus set forth the nature of the inven-l tion, what I claim herein is: l

l. A small portable sewing machine of the family type having a hollow box bed and overhanging bracket-arm, an electric motor mounted in said bed, a main-shaft journaled in said bed and driven by said motor at twice stitching speed, a reciprocatory needle carried by said bracketarm and driven at stitching speed by said mainshaft, a. vertical axis rotary hook disposed in said bed with its axis in a vertical plane containing the axis of said main-shaft, a countershaft in said plane below and parallel to the axis of the mainshaft and bevel-geared at one end to the vertical hook-shaft, a spur-gear on said main-shaft, a spur-gear on said countershaft meshing with the spur-gear on the main-shaft and having double the face width of the last mentioned spur-gear, feeding mechanism including a feed-shaft journaled at one side of said vertical plane, a large spur-gear on said feed-shaft laterally oifset from the spur-gear on the main-shaft and meshing with the` spur gear on the countershaft which drives said rotary hook, so that the feed-shaft is driven at stitching speed by the hook-driving countersha'ft.

2. In a sewing machine, a frame including a hollow box bed and overhanging bracket-arm, a main-shaft journaled high in said bed, a handwheel and'belt-pulley on said main-shaft externally of said bed, a reciprocatory needle carried by said bracket-arm and driven by said mainshaft, a vertical axis rotary hook-shaft journaled in said bed, a hook-driving countershaft journaled lowin said bed and geared at one end to the vertical hook-shaft, intermeshing one-to-one spur-gears on the main-shaft and countershaft, respectively, work-feeding mechanism including a feed-shaft, and a spur-gear on the feed-shaft of twice the pitch-diameter of the spur-gear on the hook-drivingcountershaft and meshing with said last mentioned spur-gear.

3. In a sewing machine, a frame including a flat box bed and overhanging bracket-arm, a main-shaft journaled horizontally and high in said bed in front of a longitudinal central vertical plane cutting said bed, a reciprocatory needle carried by said bracket-arm and driven by said mainshaft, a vertical-axis rotary-hook shaft journaled in said bed in front of said vertical plane, a hookdriving countershaft journaled horizontally and -low in said bed and geared to the vertical hookdriving shaft, a spur-gear on the main-shaft, a spur-gear on the hook-driving countershaft in mesh with the spur-gear on the main-shaft, a work-feeding mechanism including a feed-shaft disposed horizontally at an elevation intermediate the levels of the main-shaft and hook-driving countershaft and in rear of said last two mentioned shafts, and a large gear on the feed-shaft meshing with thegear on said hook-driving countershaft.

4. A sewing machine having a flat hollow box bed constructed with a transverse internal partition wall and an internal bearing bracket spaced from said partition wall, a rotary hook driving countershaft and a feed-shaft journaled in parallelism in said partition wall and bearing bracket and geared together so that the feed-shaft will make one revolution to two` revolutions of the hook-driving countershaft, a main-shaft journaled in said bearing bracket and one of the end walls of said bed, and a gear on said main-shaft meshing one-to-one with the gear on the hookdriving countershaft.

GEORGE A. FLECKENSTEIN. 

